Gu-nam (Ha Jung-woo) is a taxi driver in China, near the east coast in the Yellow Sea region. He's of Korean ancestry, and many of his fellow Chinese-Koreans are forced to rely on illegal methods to survive, but he thinks he can pay off his mounting debts to local gangster Myun (Kim Yun-seok) by combining his taxi wages with whatever he manages to win at the Mahjong tables, though it is not working out that way. He has enough to worry about what with his wife having returned to South Korea six months ago and lost contact with him and his young daughter, so when Myun has a proposition for him he has little choice but to take it...
What starts out looking like a deprived underclass drama of the sort we had seen so many times before turned in the hands of Na Hong-jin into a high octane thriller, but that opening half hour or so provided grounds for the action later on when we are so aware of how much is at stake. Basically, if Gu-nam doesn't carry out a murder for Myun then he will see his family killed, and if he does, his debts are paid, but if you think it's going to be as simple as that (as if murder is simple) then you had another thing coming, as The Yellow Sea was the second movie from the director who had made his name internationally with offbeat thriller The Chaser.
Some of the same cast returned for this, including most memorably Kim Yun-seok, who had played the anti-hero in that previous movie and was just as memorable as the apparently superhuman Myun here. He didn't really prove his mettle till halfway through the story, as up to that point we had to follow some social conscience-raising business as the destitute Gu-nam travels across the sea of the title - which really only figures for a small fraction of the running time - along with a bunch of illegal immigrants hoping for a better life in South Korea than the one they had in China. Once in Seoul, he has to identify his target and check out the location, all to work out how he will actually go about the deed.
Yet his wife is preying on his mind, and he wants to find out what happened to her though the ten day timeslot he has to manoeuvre in doesn't give him much opportunity. That said, he'll be having far more opportunity than he reckoned on after he finally goes to the Professor's home where he is meant to execute him and bring back his thumb as proof, only to discover someone else has the same idea. Ha Jung-woo played his character as the loneliest man in the world, but only needy when it came to seeing his wife again, as at all other times he is stuck in the loner role through necessity as nobody else is prepared to assist him, not good news when his target is murdered by hitmen but he gets the blame.
It's at that stage The Yellow Sea turns from moody drama to a mounting series of increasingly tense chase scenes, so if you were enjoying the social comment you might well feel shortchanged by developments. If, on the other hand, you were having that seen it all before sense of jadedness with Gu-nam's exploits, you would doubtless be woken up the action which ensues, taking in pursuits on foot and in vehicles, but all with the taxi driver as the quarry from a variety of bad guys who want to see him dead, and the cops who want to capture him alive. In truth the police don't seem anything but incompetent here as it's the gangsters who have everything sorted out, something of a cliché in crime thrilers but better to concentrate on those who mean Gu-nam real harm to up the tension. With a notable lack of guns, it appears carving knives and hatchets are the weapon of choice, leading to what can best be termed an utter bloodbath, mainly thanks to Myun's refusal to give up. It's not subtle by those latter scenes, but memorable it is. Music by Jang Young-kyu and Lee Byung-hoon.